Block forming mold



Sept. 17, 1940- c. H. ROTHMANN BLOCK FORMING MOLD Filed Nov. 30, 1958 Nm W M W m W 0 a we. 1 a H 2 .WV 5 M w m 1 W 2 2 2 mg a 2. ,2 I

Patented Sept. 17, 1940 I UNITED STATES PATENT OFFICE 5 Claims.

This invention relates to block-forming molds, and has for one of itsobjects the production of a simple and efficient means forfacilitatingthe extraction of air fromthe plastic material while 5 the material isbeing tamped in the mold.

A further object of this'invention is the production of a simple andeflicient means for firmly clamping the pallet plate in a positionwhereby the pallet plate may produc'ea pumping action because of itsflexible nature, while the material in the mold is being tamped.

Other objects and advantages of the present invention will appearthroughout the following specification and claims.

This invention constitutes an improvement upon my previous patentrelating to Block forming molds, issued September 19, 1933, No.1,927,717.

In the drawing: a

Figure 1 is a front elevational view of the mold;

Figure 2 is a top plan view thereof 'a portion of which is broken away;v

Figure 3 is a fragmentary side elevational view of the upper portion ofthe mold;

Figure l is a vertical sectional view taken on line 4-4 of Figure 1;

Figure 5 is a horizontal sectional view taken on line 55 of Figure 1; 1

Figure 6 is an enlarged vertical sectional view taken on line 66 ofFigure 5;

Figure 7 is a diagrammatic view illustrating the manner in which thepallet plate flexes to produce a pumping'action.

By referring to the drawing, it will be seen .35 that A designates themain frame of the mold which comprises a pair of upstanding side wallsl0. Each side wall I is provided with front and rear laterally andoutwardly extending flanges H and 12. The side walls I!) are firmlybraced 40 throughout their center by means of a transversely extendingbracing member 13 which is secured to the inner faces of the walls ID inthe manner shown in'Figure intermediate the ends of the walls and thefront and rear faces thereof and this bracing member I3 is suitablyshaped to sufliciently support molds of various types. Verticallyadjustable set screws M are carried by this bracing member l3 for thepurpose of bracing the bottom plate l5, such as is illustrated in Figure4. The particular shape of the bracing member l3 by providing the offsetportion I6 will facilitate the support of the base plate when molds ofdifferent types are used, such for instance as when forming curb blockas is illustrated in my previous Patent #1,927,717. The

walls l0 may also be braced by means of suitable transverse bracingmembers H.

A shape forming moldplate I8 is supported within the mold frame A andmaybe locked in position in any convenient manner common to the trade.This plate I8 is adapted to abut against the bottom plate IS in themanner shown in Figure 5. A suitable platform I9 is carried by the rearface of the frame A, as shown in Figures 3 and 4. 0

A suitable front door 20 is hingedly secured 1 at its lower end, as at2|, to the frame A at a point below the bottom plate l5, which plate [5is secured to the door 20. This plate I5 is provided with a downwardlyextending flange 22, and this flange is bolted to the door 20 by means Iof bolts 23 extending through the apertures 24 formed in the door. Theseapertures 24 are vertically aligned to provide for the verticaladjustment of the bottom plate l5 when desired to facilitate the moldingof a block of suitable size. The door 2| is provided with a stop plate25 extending below the door, which plate is adapted to abut against thebrace l3 when the door is swung outwardly and limit the downwardmovement of the door.

It should be noted that the door 20 is of slightly less width than thefront opening 26 of the frame A, as shown in detail in Figures 1, 2, 5and 7. A relatively thin and flexible metal pallet plate Z'lfits acrossthe front opening 26 to close the opening adjacent the door 20 and thisplate 21 overhangs the front flanges ll of the side walls ill. The door20 is adapted to engage the outer face of this flexible metal plate 21in the manner shown in Figures 2 and 5 and because of the fact that thedoor 20 is of less width than the front opening 26 of the frame A, apinching action will be produced between the front corners of the sidewalls I0 and the side edges of the door 20, causing the plate 21 to bowslightly inwardly at its center and permit the plate 21 to act as adiaphragm as described in the following.

Hook brackets 28 are carried by the front flanges H of the side WallsIll near the upper ends thereof, which hook brackets 28 are providedwith upwardly extending flanges 29 which are slightly curved outwardlybehind which the clamping levers 30, which are pivotally secured, as at31, to the upper end of the door 20, are adapted to fit to provide awedging and .clamping action to draw the door 20 tightly against thepallet plate 21 and to provide the pinching action upon the plate 21between the edges of the door 20 and the corners of the side walls [0.The

mounting of the plate 2! in the manner defined is very important fromthe standpoint of the present invention because of the particularpumping action obtained while the plastic material, such as the material32, is being tamped by a tamping tool 33. The material 32 is placedbetween the mold plate I8 and the pallet plate 21 and is tampeddownwardly in a manner such as is indicated in Figure 4, and as thistamping is continued in building up the block, the pressure of the tampupon the moist material will cause the plate 21 to act in somewhat thesame manner as a diaphragm and to flex toward and away from the door orinwardly and outwardly with respect to the plastic material 32 therebyproviding a pumping action which will facilitate the extraction of airfrom the plastic material" while it is being tamped, and in this waypermit the formation of a plastic block eliminating air bubbles and airpockets and providing substantially solid plastic molded block whencompleted. This spring action simulatinga diaphragm because of theflexible nature of the plate, is possible due to the fact that the plateis clamped in position by means of a pinching action as described, andalthough 'the inward flex of the plate is very minute and is hardlyvisible to the naked eye, this vibration of the plate caused by thetamping does actually produce a pumping action across the entire area ofthe plate 21 facilitating the extraction of air from the plasticmaterial 32. While the tamping of the material will naturally extractsome of the air, the automatic pumping action of the plate will greatlyspeed up the work of extracting the air from the plastic block becauseof the pumping action and the efiect of the plate 2'! across the entirefront area of the plastic material 32 while it is being formed into aplastic block. As shown in Figure 4, the lower edge of the plate 21 isadapted to rest upon the upper face of the base plate I 5.

It should be further understood that the plate 21 may be of any suitableor desired heighth to suit the type of block which is being formed andit is highly advisable to mold the block in a manner whereby the narrowedge of the block extends in a vertical direction, this facilitatinggreatly the tamping as well as the extraction of the air.

It should be understood that certain detail changes in the mechanicalconstruction may be employed without departing from the spirit of theinvention, so long as such changes fall within the scope of the appendedclaims.

Having described the invention, what is claimed is:

1. A mold of the class described comprising a body having an open frontportion, a door constituting a front wall of said body, and a flexiblepallet plate fitting across the open front portion of said body andoverlapping portions of the body, said door engaging said pallet plateinwardly of the body for clamping the pallet plate in spanning relationacross the open front portion of the body, said plate being adapted toflex as plastic material is tamped within the body to produce a pumpingaction to facilitate the extraction of air from plastic material withinthe body.'

2. A mold of the class described comprising a body having an open frontportion, a door constituting a front wall of said body, a flexiblepallet plate fitting across the open front portion of said body andoverlapping portions of the body,

said door engaging said pallet plate inwardly of the body for clampingthe pallet plate in spanning relation across the open front portion ofthe body, said plate being adapted to flex as plastic material is tampedwithin the body to produce a pumping action to facilitate the extractionof air from plastic material within the body, and means for clampingsaid door in a closed position.

3. A mold of vithe class described comprising a body having an openfront portion, a door constituting a front wall of said body, a flexiblepallet plate fitting across the open front portion of saidbody andoverlapping portions of the body,

' said door engaging said pallet plate for clamping the pallet plateacross the open front portion of the body, said plate being adapted toflex as plastic material is tamped within the body to produce a pumpingaction to facilitate the extraction of air from plastic material withinthe body, means for clamping said door in a closed position, and saidopen front portion being of greater width than the door whereby thepallet plate will flex slightly inwardly as the door is clamped in aclosed position.

4. A mold of the class described comprising a body having an open frontportion, a door constituting a front wall of said body, and a flexiblepallet plate fitting across the open front portion of said body andoverlapping portions of the body, said door engaging said pallet platefor clamping the pallet plate-across the open front portion of the body,said plate being adapted to flex as plastic material is tamped withinthe body to produce a pumping action to facilitate the extraction of airfrom plastic material within the body, clamping levers overlying thebody and door for clamping said door in a closed position, meansreceiving the levers for holding the same in a clamping position, andsaid door engaging the pallet plate inwardly of the walls of the bodyfor flexing the plate slightly inwardly of the'body as the door isclamped in a closed position.

5. A mold of the class'described comprising a body having an open frontportion, a door constituting a front wall of said body, the open frontportion being of slightly greater width than the door, a flexible palletplate fitting across the open front portion and overlap-ping the sideedges of the body portion, cl'ampinglevers carried by the door, meanscarried by the body for receiving the levers, the levers being adaptedto be swung into engagement with said last mentioned means for tightlydrawing the door to a clamping position whereby the side portions of thepallet plate will be firmly clamped in a pinching action between theside edges of the door and the side edges of the body of the mold, thepallet plate being of CHARLES H. ROTHIWANN'.

